[Fixed]-Django ManagementForm data is missing or has been tampered with


I have meet this problem.

The reason is there is NO something like form-TOTAL_FORMS, form-INITIAL_FORMS and form-MAX_NUM_FORMS) in your POST data.

You should use {{ formset.as_p }}, this will render the management_form data from the formset. If you want to make the custom formset rendering, you should not forget the management_form of the formset to let POST data be with the mangement_form data.


When you use inline formset, you need to provide the instance that the objects relate to.

# First, fetch the instance from the db
workout = code_that_fetches_instance()

if request.method == "POST" : 
    formset = WorkoutInlineFormSet(request.POST, instance=workout)
    formset = WorkoutInlineFormSet(instance=workout)

See the example in the docs on using an inline formset in a view for more information.

If workout and exercise are your models, you should follow the python convention and rename them Workout and Exercise. Lowercase workout should be the instance that all the exercises in your formset are linked to.


Change this:

  formset = WorkoutInlineFormSet(request.POST)

to this:

 formset = WorkoutInlineFormSet(request.POST or None, request.FILES or None)

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